CN110267908B

CN110267908B - MEMS actuation system and method

Info

Publication number: CN110267908B
Application number: CN201780068626.8A
Authority: CN
Inventors: 刘晓蕾; M·伍; 王桂芹
Original assignee: Maestro Microelectronics Nanjing Co ltd
Current assignee: Maestro Microelectronics Nanjing Co ltd
Priority date: 2016-09-12
Filing date: 2017-09-08
Publication date: 2023-08-22
Anticipated expiration: 2037-09-08
Also published as: US20180076737A1; US20180072562A1; US11254558B2; CN110574502B; US11274033B2; WO2018049181A1; US10523135B2; CN110582828B; WO2018049147A1; US10875761B2; WO2018049161A1; US20180072565A1; CN110291434B; US11279612B2; US20180076739A1; US10807857B2; CN110574502A; CN110582828A; CN110291434A; US20180076740A1

Abstract

A microelectromechanical system (MEMS) actuator includes a first set of actuating fingers, a second set of actuating fingers, and a first cross-over structure configured to connect at least two fingers of the first set of actuating fingers. While bridging at least one finger of the second set of actuating fingers.

Description

MEMS actuation system and method

Related cases

The application claims the benefit of the following U.S. provisional applications: 62/393,436 submitted on month 9 and 12 of 2016, 62/393,419 submitted on month 9 and 12 of 2016, 62/419,117 submitted on month 11 and 8 of 2016, 62/419,814 submitted on month 11 and 9 of 2016, and 62/420,960 submitted on month 11 and 11 of 2016; the contents of which are incorporated by reference into the present application.

Technical Field

The present disclosure relates generally to actuators, and more particularly, to miniaturized MEMS actuators configured for use within camera packages.

Background

As is known in the art, actuators may be used to convert an electronic signal into mechanical motion. In many applications such as portable devices, imaging-related devices, telecommunications components, and medical instruments, it may be beneficial for the microactuator to fit within these applications, which are small in size, low in power, and limited in cost.

Microelectromechanical Systems (MEMS) technology can be defined in its most general form as the technology of miniaturized mechanical and electromechanical elements manufactured using micromachining technology. The critical dimensions of MEMS devices can vary from well below 1 micron to a few millimeters. In general, MEMS actuators are more compact than conventional actuators, and they consume less power.

Disclosure of Invention

Invention #1

In one embodiment, a microelectromechanical system (MEMS) actuator includes a first set of actuation fingers, a second set of actuation fingers, and a first cross-over structure configured to connect at least two fingers of the first set of actuation fingers. While bridging at least one finger of the second set of actuating fingers.

The following features may include one or more of them. The first bridging structure may be configured to bridge at least one finger of the second set of actuation fingers by a distance configured to define a maximum level of first axis/first direction deflection of the at least one finger of the second set of actuation fingers. The first bridging structure may be configured to define a first gap between the first bridging structure and at least one finger of the second set of actuation fingers, wherein the first gap is in the range of 0.1 μm and 5 μm. The second bridging structure may be configured to connect at least two fingers of the second set of actuation fingers while bridging at least one finger of the first set of actuation fingers. The second bridging structure may be configured to bridge at least one finger of the first set of actuation fingers by a distance configured to define a maximum level of first axis/second direction deflection of at least two fingers of the second set of actuation fingers. The first bridging structure may be configured to define a first gap between the first bridging structure and at least one finger of the second set of actuation fingers, wherein the first gap may be in the range of 0.1 μm and 5 μm. The first set of actuation fingers may be a set of fixed actuation fingers. The second set of actuating fingers may be a set of movable actuating fingers. The second set of actuation fingers may be bi-directionally displaceable on the second axis and substantially non-displaceable on the third axis. The first set of actuation fingers may be constructed of a silicon material. The second set of actuation fingers may be constructed of a silicon material. The first bridging structure may be constructed of a metallic material. The second bridging structure may be constructed of a metallic material.

In another embodiment, a microelectromechanical system (MEMS) actuator includes a first set of actuation fingers, a second set of actuation fingers, and a first bridging structure configured to connect at least two fingers of the first set of actuation fingers while bridging at least one finger of the second set of actuation fingers, wherein: the first bridging structure is configured to span at least one finger of the second set of actuating fingers at a distance configured to define a maximum level of first axis/first direction deflection of the at least one finger of the second set of actuating fingers, and the first bridging structure is configured to define a first gap between the first bridging structure and the at least one finger of the second set of actuating fingers, wherein the first gap is in the range of 0.1 μm and 5 μm.

The following features may include one or more of them. The second bridging structure may be configured to connect at least two fingers of the second set of actuation fingers while bridging at least one finger of the first set of actuation fingers. The second bridging structure may be configured to bridge at least one finger of the first set of actuation fingers by a distance configured to define a maximum level of first axis/second direction deflection of at least two fingers of the second set of actuation fingers. The first bridging structure may be configured to define a first gap between the first bridging structure and at least one finger of the second set of actuation fingers, wherein the first gap may be in the range of 0.1 μm and 5 μm.

In another embodiment, a microelectromechanical system (MEMS) actuator includes a first set of actuation fingers, a second set of actuation fingers, and a first bridging structure configured to connect at least two fingers of the first set of actuation fingers while bridging at least one finger of the second set of actuation fingers, wherein: the first bridging structure is configured to span at least one finger of the second set of actuating fingers at a distance configured to define a maximum level of first axis/first direction deflection of the at least one finger of the second set of actuating fingers, and the first bridging structure is configured to define a first gap between the first bridging structure and the at least one finger of the second set of actuating fingers, wherein the first gap is in the range of 0.1 μm and 5 μm. The second bridging structure is configured to connect at least two fingers of the second set of actuation fingers while bridging at least one finger of the first set of actuation fingers, wherein: the second bridging structure is configured to bridge at least one finger of the first set of actuating fingers at a distance configured to define a maximum level of first axis/second direction deflection of at least two fingers of the second set of actuating fingers, and the first bridging structure is configured to define a first gap between the first bridging structure and at least one finger of the second set of actuating fingers, wherein the first gap is in the range of 0.1 μm and 5 μm.

The following features may include one or more of them. The first set of actuation fingers may be a set of fixed actuation fingers. The second set of actuating fingers may be a set of movable actuating fingers.

One or more embodiments are specifically described in the following drawings and description. Other features and advantages will be apparent from the description and drawings, and from the claims.

Drawings

FIG. 1 is a perspective view of a package according to various embodiments of the present disclosure;

FIG. 2A is a schematic diagram of an in-plane MEMS actuator with an optoelectronic device according to various embodiments of the present disclosure;

FIG. 2B is a perspective view of an in-plane MEMS actuator with an optoelectronic device in accordance with various embodiments of the present disclosure;

FIG. 3A is a schematic diagram of an in-plane MEMS actuator according to various embodiments of the present disclosure;

3B-3C are schematic diagrams of connection assemblies included within the in-plane MEMS actuator of FIG. 3A, according to various embodiments of the present disclosure;

FIG. 4 is a schematic diagram of a comb drive sector according to various embodiments of the present disclosure;

FIG. 5 is a schematic illustration of a comb pair according to various embodiments of the present disclosure;

FIG. 6A is a schematic illustration of fingers of the comb-teeth pair of FIG. 5, according to various embodiments of the present disclosure;

6B-6F are schematic diagrams of cantilever-stress reduction systems according to various embodiments of the present disclosure;

6G-6L are schematic diagrams of finger array buffering (snubbing) systems according to various embodiments of the present disclosure;

FIG. 7 is a schematic diagram of a combination of an in-plane MEMS actuator and an out-of-plane actuator in accordance with various embodiments of the present disclosure;

FIG. 8 is a schematic diagram of an out-of-plane actuator according to various embodiments of the present disclosure;

FIG. 9A is a cross-sectional view of a two-actuator package according to various embodiments of the present disclosure;

FIG. 9B is a cross-sectional detail of a two-actuator package according to various embodiments of the present disclosure;

FIG. 10 is a cross-sectional detail of a modified out-of-plane actuator according to various embodiments of the present disclosure;

FIG. 11 is a cross-sectional view of an actuator beam of the modified out-of-plane actuator of FIG. 10 in accordance with various embodiments of the present disclosure;

FIG. 12 is a cross-sectional view of a package including a single actuator according to various embodiments of the present disclosure;

13A-13B are perspective views of a retainer assembly according to various embodiments of the present disclosure;

FIG. 14 is a flow chart of a method of assembling a package including a single actuator, according to various embodiments of the present disclosure;

FIG. 15 is a flowchart of a method of assembling a package including a plurality of actuators according to various embodiments of the present disclosure;

FIG. 16 is a schematic view of a zipper actuator according to various embodiments of the present disclosure;

17A-17C are schematic views of alternative embodiments of the zipper actuator of FIG. 16, in accordance with various embodiments of the present disclosure;

18A-18B are schematic views of alternative embodiments of the zipper actuator of FIG. 16, in accordance with various embodiments of the present disclosure;

19A-19C are schematic illustrations of a slidable connection assembly according to various embodiments of the present disclosure;

like reference symbols in the various drawings indicate like elements.

Detailed Description

System overview:

referring to fig. 1, a MEMS package 10 is shown in accordance with aspects of the present disclosure. In this example, the package 10 is shown to include a printed circuit board 12, a microelectromechanical system (MEMS) assembly 14, a drive circuit 16, electronic components 18, a flex circuit 20, and an electrical connector 22. Microelectromechanical System (MEMS) assembly 14 may include a microelectromechanical system (MEMS) actuator 24 and an optoelectronic device 26 mounted to microelectromechanical system (MEMS) actuator 24.

Examples of Microelectromechanical System (MEMS) actuators 24 may include, but are not limited to, in-plane MEMS actuators, out-of-plane MEMS actuators, and combinations of in-plane/out-of-plane MEMS actuators. For example, if microelectromechanical system (MEMS) actuator 24 is an in-plane MEMS actuator, the in-plane MEMS actuator may include an electrostatic comb drive actuation system (discussed in more detail below). Additionally, if the microelectromechanical system (MEMS) actuator 24 is an out-of-plane MEMS actuator, the out-of-plane MEMS actuator may include a piezoelectric actuation system or an electrostatic actuation. And if microelectromechanical system (MEMS) actuator 24 is an in-plane/out-of-plane hybrid MEMS actuator, the combination of in-plane/out-of-plane MEMS actuators may include an electrostatic comb drive actuation system and a piezoelectric actuation system.

Examples of optoelectronic devices 26, as discussed in more detail below, may include, but are not limited to, image sensors, holder assemblies, UV filters, auto-focus assemblies, and/or lens assemblies. Examples of electronic components 18 may include, but are not limited to, various electronic or semiconductor components and devices. The flex circuit 20 and/or connector 22 may be configured to electrically connect the MEMS package 10 to, for example, a smart phone or digital camera (shown as superordinate item 28).

As will be discussed in greater detail below, the microelectromechanical system (MEMS) actuator 24 may be sized to fit within a recess of the printed circuit board 12. The depth of this recess in the printed circuit board 12 may vary depending on the particular embodiment and the physical dimensions of the microelectromechanical system (MEMS) actuator 24.

In some embodiments, some elements of the MEMS package 10 may be connected together using various epoxy/adhesives. For example, as will be discussed in greater detail below, the outer frame of the microelectromechanical system (MEMS) actuator 24 may include contact pads, which may correspond to similar contact pads on the printed circuit board 12.

Referring also to FIG. 2A, a microelectromechanical system (MEMS) assembly 14 is shown that may include an optoelectronic device 26 mounted to a microelectromechanical system (MEMS) actuator 24. A microelectromechanical system (MEMS) actuator 24 may include an outer frame 30, a plurality of conductive flexures 32, a MEMS actuation core 34 for attaching a payload (e.g., a device), and an attached optoelectronic device 26. The optoelectronic device 26 may be secured to a microelectromechanical system (MEMS) actuation core 34 of the MEMS actuator 24 by epoxy (or various other adhesives/materials and/or bonding methods).

Referring also to FIG. 2B, the plurality of conductive flexures 32 of the microelectromechanical system (MEMS) actuator 24 may bend and yield upward to achieve a desired level of flexibility. In the illustrated embodiment, the plurality of conductive flexures 32 may have one end connected to a MEMS actuation core 34 (e.g., a moving portion of a microelectromechanical system (MEMS) actuator 24) and another end connected to an outer frame 30 (e.g., a stationary portion of a MEMS actuator 24).

The plurality of conductive flexures 32 may be conductive wires that may extend above a plane (e.g., an upper surface) of the microelectromechanical system (MEMS) actuator 24 and may electrically connect laterally separated elements of the MEMS actuator 24. For example, the plurality of conductive flexures 32 may provide electrical signals from the opto-electronic device 26 and/or the MEMS actuation core 34 to the outer frame 30 of the microelectromechanical system (MEMS) actuator 24. As described above, the outer frame 30 of the microelectromechanical system (MEMS) actuator 24 may be secured to the circuit board 12 using an epoxy (or various other adhesive materials or devices).

Referring also to fig. 3A, a top view of a microelectromechanical system (MEMS) actuator 24 is shown, in accordance with various embodiments of the present disclosure. The outer frame 30 is shown to include (in this example) four frame assemblies (e.g., frame assembly 100A, frame assembly 100B, frame assembly 100C, frame assembly 100D), which are separated in the figures for additional detail. However, during assembly, the frame assemblies 100A, 100B, 100C, and 100D may be connected (or locked) together to form the outer frame 30 (discussed in more detail below). Conversely, in other embodiments, frame assemblies 100A, 100B, 100C, and 100D may not be connected together and may be separate assemblies (although this is typically not the case).

The outer frame 30 of the microelectromechanical system (MEMS) actuator 24 may include a plurality of contact pads (e.g., contact pad 102A on frame assembly 100A, contact pad 102B on frame assembly 100B, contact pad 102C on frame assembly 100C, and contact pad 102D on frame assembly 100D, which may be electrically connected to one end of a plurality of conductive flexures 32. The conductive flexures 32 are provided for illustration purposes only and while one possible embodiment is shown, other configurations are possible and should be considered to be within the scope of this disclosure.

The MEMS actuation core 34 may include a plurality of contact pads (e.g., contact pad 104A, contact pad 104B, contact pad 104C, contact pad 104D) that may be electrically connected to the other ends of the plurality of conductive flexures 32. A portion of the contact pads (e.g., contact pad 104A, contact pad 104B, contact pad 104C, contact pad 104D) of the MEMS actuation core 34 may be electrically connected to the photovoltaic device 26 by wire bonding, silver paste, or eutectic seal, thereby making electrical connection of the photovoltaic device 26 to the outer frame 30.

MEMS actuation core 34 may include one or more comb drive sectors (e.g., comb drive sector 106), which are actuation sectors disposed within microelectromechanical system (MEMS) actuator 24. Comb drive sectors (e.g., comb drive sector 106) within MEMS actuation core 34 may be disposed in the same plane and may be positioned orthogonal to each other to effect movement in two axes (e.g., x-axis and y-axis).

Although in this particular example, MEMS actuation core 34 is shown to include four comb drive sectors, this is for illustrative purposes only and is not intended to limit the present disclosure, as other configurations are possible. For example, the number of comb drive sectors may be increased or decreased according to design criteria.

Although in this particular example, the four comb drive sectors are shown as being generally square in shape, this is for illustrative purposes only and is not intended to limit the present disclosure as other configurations are possible. For example, the shape of the comb drive sector can be varied to meet various design criteria.

Each comb drive sector (e.g., comb drive sector 106) within MEMS actuation core 34 may include one or more moving portions and one or more fixed portions. As will be discussed in greater detail below, a comb drive sector (e.g., comb drive sector 106) within MEMS actuation core 34 may be connected to a periphery 110 of MEMS actuation core 34 (i.e., a portion of MEMS actuation core 34 including contact pads 104A, 104B, 104C, 104D) via a cantilever assembly (e.g., cantilever assembly 108), which is a portion of MEMS actuation core 34 that may be connected to optoelectronic device 26, thereby enabling transmission of motion to optoelectronic device 26.

Multi-piece outer frame (invention # 6)

As described above, the illustrated outer frame 30 includes (in this example) four frame assemblies (e.g., frame assembly 100A, frame assembly 100B, frame assembly 100C, frame assembly 100D), which are separated in the figures, for additional detail. However, during assembly, the frame assemblies 100A, 100B, 100C, and 100D may be connected together to form the outer frame 30.

Thus, referring also to fig. 3B-3C, the microelectromechanical system (MEMS) actuator 24 may include a MEMS actuation core 34, and a multi-piece MEMS electrical connector assembly (e.g., the outer frame 30) electrically connected to the MEMS actuation core 34 and configured to be electrically connected to the printed circuit board 12. The multi-piece MEMS electrical connector (e.g., the outer frame 30) may include: a plurality of sub-elements (e.g., frame assembly 100A, frame assembly 100B, frame assembly 100C, frame assembly 100D), and a plurality of connection assemblies (e.g., connection assemblies 112) configured to connect the plurality of sub-elements together (e.g., frame assembly 100A, frame assembly 100B, frame assembly 100C, frame assembly 100D).

While figures 3B-3C only show frame assembly 100A and frame assembly 100D connected together using connection assembly 112 for illustrative purposes only. For example, frame assembly 100A and frame assembly 100B may be connected using another connection assembly; the frame assembly 100B and the frame assembly 100C may be connected using another connection assembly; the frame assembly 100C and the frame assembly 100D may be connected using another connection assembly.

As described above, the plurality of conductive flexures 32 of the microelectromechanical system (MEMS) actuator 24 may bend upward and yield to achieve a desired level of flexibility. In particular, when multiple sub-elements (e.g., frame assembly 100A, frame assembly 100B, frame assembly 100C, frame assembly 100D) are disengaged, the multiple conductive flexures 32 may be configured in a generally flat shape. And the frame assemblies 100A, 100B, 100C, 100D may be connected together prior to attaching the microelectromechanical system (MEMS) actuator 24 to the printed circuit board 12. Further, when multiple sub-elements (e.g., frame assembly 100A, frame assembly 100B, frame assembly 100C, frame assembly 100D) are connected together, the plurality of conductive flexures 32 may be configured in a generally arcuate shape.

The plurality of connection assemblies (e.g., connection assembly 112) may include a latch 114 and a locking buckle 116 configured to engage the latch 114. Each locking buckle 116 may include a toggle spring 118 for engaging a recess of the locking tongue 114. In addition, each locking bolt 114 may include a push spring 120 configured to bias the recess of the locking bolt 114 against the toggle spring 118.

As will be discussed in more detail below, the multi-piece MEMS electrical connector assembly (e.g., the outer frame 30) may be configured to be rigidly attached to and wirebonded to the printed circuit board 12 by a plurality of wirebond connections, which may be encapsulated in epoxy for added strength and durability.

Referring also to fig. 4, a top view of the comb drive sector 106 is shown, according to various embodiments of the present disclosure. Each comb drive sector (e.g., comb drive sector 106) may include one or more motion control cantilever assemblies (e.g., motion control cantilever assemblies 150A, 150B) located outside of comb drive sector 106, a movable frame 152, a movable spine 154, a fixed frame 156, a fixed spine 158, and a cantilever assembly 108 configured to connect movable frame 152 to periphery 110 of MEMS actuation core 34. In this particular configuration, the motion control cantilever assemblies 150A, 150B may be configured to prevent y-axis displacement between the moving frame 152/movable spine 154 and the fixed frame 156/fixed spine 158.

Comb drive sector 106 can include a movable member that includes a movable frame 152 and a plurality of movable ridges 154 that are generally orthogonal to movable frame 152. Comb drive sector 106 can also include a securing member that includes a securing frame 156 and a plurality of securing ridges 158 that are generally orthogonal to securing frame 156. The cantilever assembly 108 may be deformed in one direction (e.g., in response to y-axis deflection loads) and rigid in another direction (e.g., in response to x-axis tension and compression loads) to achieve absorption of motion by the cantilever assembly 108 in the y-axis, but transfer of motion in the x-axis.

Referring also to FIG. 5, a detailed view of portion 160 of comb drive sector 106 is shown. The movable ridges 154A, 154B may include a plurality of discrete movable actuation fingers that are generally orthogonally connected with the movable ridges 154A, 154B. For example, the illustrated movable ridge 154A includes a movable actuation finger 162A, and the illustrated movable ridge 154B includes a movable actuation finger 162B.

Further, the stationary ridge 158 may include a plurality of discrete stationary actuation fingers that are generally orthogonally attached to the stationary ridge 158. For example, the illustrated stationary ridge 158 includes a stationary actuation finger 164A that is configured to engage and interact with the movable actuation finger 162A. In addition, the illustrated stationary ridge 158 includes a stationary actuation finger 164B that is configured to engage and interact with the movable actuation finger 162B.

Thus, various numbers of actuation fingers can be associated (i.e., connected) with the movable ridges (e.g., movable ridges 154A, 154B) and/or the fixed ridges (e.g., fixed ridges 158) of the comb drive sector 106. As described above, each comb drive sector (e.g., comb drive sector 106) may include two motion control cantilever assemblies 150A, 150B, one disposed on each side of comb drive sector 106. Each of the two motion control cantilever assemblies 150A, 150B may be configured to connect the movable frame 152 and the fixed frame 156 because such a configuration enables the movable actuation fingers 162A, 162B to be displaced in the x-axis relative to the fixed actuation fingers 164A, 164B (respectively) while preventing the movable actuation fingers 162A, 162B from being displaced in the y-axis and contacting the fixed actuation fingers 164A, 164B (respectively).

Although the actuation fingers 162A, 162B, 164A, 164B (or at least the central axes of the actuation fingers 162A, 162B, 164A, 164B) are shown as being generally parallel to each other and generally orthogonal to the respective ridges to which they are connected, this is for illustrative purposes only and is not intended to limit the present disclosure as other configurations are possible. Moreover, in some embodiments, the actuation fingers 162A, 162B, 164A, 164B may have the same width throughout their length, and in other embodiments, the actuation fingers 162A, 162B, 164A, 164B may be tapered.

Further, in some embodiments, movable frame 152 may be displaced in the positive x-axis direction when a voltage potential is applied between actuating finger 162A and actuating finger 164A, and movable frame 152 may be displaced in the negative x-axis direction when a voltage potential is applied between actuating finger 162B and actuating finger 164B.

Referring also to FIG. 6A, a detailed view of portion 200 of comb drive sector 106 is shown. The fixed spine 158 may be generally parallel to the movable spine 154B, wherein the actuation fingers 164B and 162B may overlap within the region 202, wherein the width of the overlapping region 202 is typically in the range of 10-50 microns. Although the overlap region 202 is described as being in the range of 10-50 microns, this is for illustration purposes only and is not intended to limit the present disclosure as other configurations are possible.

The overlap region 202 may represent a distance 204 through which the end of the actuation finger 162B extends and overlaps the end of the actuation finger 164B, with the actuation finger interposed therebetween. In some embodiments, the actuation fingers 162B and 164B may be tapered such that their respective tips are narrower than their respective bases (i.e., where they attach to their ridges). As is known in the art, various degrees of taper may be employed with respect to actuation fingers 162B and actuation fingers 164B. Additionally, the overlap of actuation fingers 162B and 164B provided by overlap region 202 may help ensure that there is sufficient initial actuation force when a voltage potential is applied so that MEMS actuation core 34 may move gradually and smoothly without any abrupt jump when the applied voltage is changed. The height of the actuation fingers 162B and 164B may be determined by various aspects of the MEMS fabrication process and various design criteria.

The length 206 of the actuation fingers 162B and 164B, the size of the overlap region 202, the gap between adjacent actuation fingers, and the taper angle of the actuation fingers incorporated into the various embodiments may be determined by various design criteria, application considerations, and manufacturability considerations, which may be optimized to achieve the desired displacement with the available voltage potential.

Cantilever stress reduction system (invention # 2)

As described above, the cantilever assembly 108 may be configured to connect the moving frame 152 of the comb drive sector 106 and the periphery 110 of the MEMS actuation core 34. Referring also to fig. 6B-6E, to mitigate the effects of any z-axis impact load to which the cantilever assembly 108 is subjected, a cantilever stress reduction system may be used. For example, the cantilever assembly 108 may include: an intermediate cantilever portion 208; a main cantilever 210 configured to connect the movable portion of the microelectromechanical system (MEMS) actuator 24 and the intermediate cantilever portion 208; a plurality of intermediate links (e.g., intermediate links 212, 214, 216, 218) configured to connect the intermediate cantilever portion 208 to a portion of a microelectromechanical system (MEMS) actuator 24.

For example, the cantilever stress reduction system shown in fig. 6B includes intermediate links 212, 214; the cantilever stress reduction system shown in fig. 6C includes intermediate links 212, 214; the cantilever stress reduction system shown in fig. 6D includes intermediate links 212, 214, 216, 218; and the cantilever stress reduction system shown in fig. 6E includes intermediate links 212, 214. Some or all of the plurality of intermediate links 212, 214, 216, 218 may be connected to movable portions of the microelectromechanical system (MEMS) actuator 24 (e.g., the movable frame 152 and the movable ridge 154) or to non-movable portions of the microelectromechanical system (MEMS) actuator 24 (e.g., the periphery 110).

In some embodiments, the main cantilever 210 may include a first distal end connected to a movable portion (e.g., the movable frame 152 and the movable ridge 154) of the microelectromechanical system (MEMS) actuator 24 and a second distal end connected to the intermediate cantilever portion 208.

Some embodiments of the plurality of intermediate links 212, 214, 216, 218 may include two intermediate links (e.g., intermediate links 212, 214) configured non-parallel to the main boom 210 (as shown in fig. 6B, 6C, and 6E), or substantially perpendicular to the main boom 210 (as shown in fig. 6B and 6E). Other embodiments of the plurality of intermediate links 212, 214, 216, 218 may include four intermediate links configured non-parallel to the main boom 210 (as shown in fig. 6D).

In particular, the plurality of intermediate links 212, 214, 216, 218 may be configured to absorb out-of-plane (z-axis) motion of the movable portions (e.g., the movable frame 152 and the movable spine 154) of the microelectromechanical system (MEMS) actuator 24. For example, some or all of the plurality of intermediate links 212, 214, 216, 218 may be configured to twist to absorb out-of-plane (z-axis) motion of the movable portions (e.g., the movable frame 152 and the movable ridge 154) of the microelectromechanical system (MEMS) actuator 24. To provide additional strength, the planar bridging structure 220 may be configured to connect the upper surface of the intermediate cantilever portion 208 to the upper surface of one or more of the plurality of intermediate links 212, 214, 216, 218. Planar bridge structure 220 may be fabricated by depositing a layer of material (e.g., polysilicon, metal (e.g., aluminum, titanium, copper, tungsten), amorphous diamond, oxide (e.g., silicon oxide, aluminum oxide, or other metal oxide), nitride (e.g., silicon nitride, metal nitride), carbide (e.g., silicon carbide, metal carbide), etc., or a combination thereof) to bridge an upper surface of intermediate cantilever portion 208 and an upper surface of one or more of the plurality of intermediate links 212, 214, 216, 218.

As described above, to mitigate the effects of any z-axis impact load to which the cantilever assembly 108 is subjected, a cantilever stress reduction system may be used. In the embodiment shown in fig. 6A-6E, the illustrated cantilever assembly 108 includes: an intermediate cantilever portion 208; a main cantilever 210 configured to connect the movable portion of the microelectromechanical system (MEMS) actuator 24 and the intermediate cantilever portion 208; a plurality of intermediate links (e.g., intermediate links 212, 214, 216, 218) configured to connect the intermediate cantilever portion 208 to a portion of a microelectromechanical system (MEMS) actuator 24.

Therefore, it should be understood that other configurations are possible and should be considered to be within the scope of the present disclosure and claims. For example, the cantilever stress reduction system described above may be used on each end of the cantilever assembly 108. Thus, each end of the main cantilever 210 may be connected to an intermediate cantilever portion (e.g., intermediate cantilever portion 208), wherein a first of these intermediate cantilever portions may be used to connect a first end of the main cantilever 210 (of the cantilever assembly 108) to the moving frame 152 and a second of these intermediate cantilever portions may be used to connect a second end of the main cantilever 210 (of the cantilever assembly 108) to the periphery 110 of the MEMS actuation core 34.

Finger array buffer (invention # 1)

As described above, microelectromechanical system (MEMS) actuator 24 may include a plurality of actuation fingers including movable actuation finger 162B (connected to movable frame 152 and movable ridge 154B) and fixed actuation finger 164B (connected to fixed frame 156 and fixed ridge 158). As described above, the movable actuation finger 162B is displaceable along the x-axis and substantially non-displaceable along the y-axis.

Referring also to fig. 6F-6H, to mitigate the effects of any z-axis impact load experienced by the plurality of actuation fingers and any deformation experienced by the motion control cantilever, a finger array buffer system 222 may be utilized to mitigate displacement along the z-axis. Microelectromechanical System (MEMS) actuator 24 may include a first set of actuation fingers (e.g., movable actuation fingers 162B1, 162B2, 162B 3) and a second set of actuation fingers (e.g., fixed actuation fingers 164B1, 164B2, 164B 3), wherein these actuation fingers may be composed of silicon (or any other suitable material).

The first bridging structure (e.g., bridging structure 224) is configured to connect at least two fingers (e.g., actuating fingers 162B1, 162B 2) of the first set of actuating fingers (e.g., movable actuating fingers 162B1, 162B2, 162B 3) and to bridge at least one finger (e.g., actuating finger 164B 1) of the second set of actuating fingers (e.g., fixed actuating fingers 164B1, 164B2, 164B 3). The first cross-over structure 224 may be composed of a metallic material, examples of which may include, but are not limited to, polysilicon, metal (e.g., aluminum, titanium, copper, tungsten), amorphous diamond, oxide (e.g., silicon oxide, aluminum oxide, or other metal oxide), nitride (e.g., silicon nitride, metal nitride), carbide (e.g., silicon carbide, metal carbide), etc., or a combination thereof.

The first bridging structure 224 may be configured to bridge at least one finger (e.g., actuating finger 164B 1) of the second set of actuating fingers (e.g., fixed actuating fingers 164B1, 164B2, 164B 3) by a distance configured to define a maximum degree of first axis/first direction (i.e., z-axis) deflection for at least one finger (e.g., actuating finger 164B 1) of the second set of actuating fingers (e.g., fixed actuating fingers 164B1, 164B2, 164B 3). The first cross-linking structure 224 may be configured to define a gap between the first cross-linking structure 224 and at least one finger (e.g., the actuation finger 164B 1) of the second set of actuation fingers (e.g., the fixed actuation fingers 164B1, 164B2, 164B 3), wherein the gap is in the range of 0.1 μm and 5 μm.

The second bridging structure 228 may be configured to connect at least two fingers (e.g., actuation fingers 164B2, 164B 3) of the second set of actuation fingers (e.g., fixed actuation fingers 164B1, 164B2, 164B 3) while bridging at least one finger (e.g., actuation finger 162B 3) of the first set of actuation fingers (e.g., movable actuation fingers 162B1, 162B2, 162B 3). The second bridging structure 228 may be composed of a metallic material, examples of which may include, but are not limited to, polysilicon, metal (e.g., aluminum, titanium, copper, tungsten), amorphous diamond, oxide (e.g., silicon oxide, aluminum oxide, or other metal oxide), nitride (e.g., silicon nitride, metal nitride), carbide (e.g., silicon carbide, metal carbide), etc., or a combination thereof.

The second bridging structure 228 may be configured to bridge at least one finger (e.g., actuating finger 162B 3) of the first set of actuating fingers (e.g., movable actuating fingers 162B1, 162B2, 162B 3) by a distance configured to define a maximum degree of first axis/second direction (i.e., z axis) deflection for at least two fingers (e.g., actuating fingers 164B2, 164B 3) of the second set of actuating fingers (e.g., fixed actuating fingers 164B1, 164B2, 164B 3). The second bridging structure 228 may be configured to define a gap between the second bridging structure 228 and at least one finger (e.g., actuating finger 162B 3) of the first set of actuating fingers (e.g., movable fingers 162B1, 162B2, 162B 3), wherein the gap may be in the range of 0.1 μm and 5 μm.

In fabricating the first and second bridging structures 224, 228, a film patch may be deposited on top of the overlapping area of the finger arrays (e.g., movable actuation fingers 162B and fixed actuation fingers 164B). Specifically, a film patch may be attached to bridge three fingers (e.g., actuating fingers 162B1, 162B2, and 164B1 for first bridge 224), wherein the film is separated from (in this example) actuating finger 164B1 such that the movable finger (e.g., actuating finger 164B 1) is movable within an allowable x-axis range.

Thus, for the first cross-over structure 224, the movable actuation fingers 162B1, 162B2 may be prevented from moving downward (i.e., into the page). And for the second bridging structure 228, the movable actuation finger 162B3 will be prevented from moving upward (i.e., out of the page).

The sacrificial layer 232 may be composed of various materials (e.g., polysilicon, metal, oxide, nitride, carbide, and polymer (e.g., PMMA, parylene, etc.)) and may be removed during release and may leave the above-described gap that controls the maximum deflection of the z-axis that may be experienced by, for example, the movable actuation fingers 162B1, 162B2, 162B 3.

As described above, examples of microelectromechanical system (MEMS) actuators 24 may include, but are not limited to, in-plane MEMS actuators, out-of-plane MEMS actuators, and combinations of in-plane/out-of-plane MEMS actuators. Referring also to fig. 7, there is shown an in-plane/out-of-plane MEMS actuator combination comprising an in-plane MEMS actuator 250 to which an out-of-plane actuator 252 is attached. As described above (and shown in fig. 3), microelectromechanical system (MEMS) actuator 24 may include four comb drive sectors (e.g., comb drive sector 106), wherein out-of-plane actuator 252 may be positioned in the center of these comb drive sectors. Thus, the out-of-plane actuator 252 may be located below the in-plane MEMS actuator 250 and/or the outer frame 30 of the in-plane MEMS actuator 250.

The plurality of conductive flexures 32 may be configured to conduct electrical signals within the in-plane MEMS actuator 250 and may also provide electrical signal routing to the out-of-plane actuator 252. The plurality of conductive flexures 32 may be highly conductive and may be formed of metal alloy layers (e.g., aluminum, copper, metals, and metal alloys) disposed on a plurality of layers, including but not limited to polysilicon, silicon oxide, silicon, or other suitable semiconductor surfaces.

The plurality of conductive flexures 32 may be designed to provide a low level of stiffness to achieve x-axis and y-axis and/or z-axis motion to provide the desired degrees of freedom for the in-plane MEMS actuator 250 and/or the out-of-plane actuator 252.

While the illustrated bridging structures (e.g., first bridging structure 224 and second bridging structure 228) are substantially rectangular bridging structures bridging a single actuation finger, this is for illustration purposes only and is not intended to limit the present disclosure as other configurations are possible and should be considered within the scope of the present disclosure. For example, referring also to fig. 6I-6L, other embodiments of bridging structures (e.g., first bridging structure 224 and second bridging structure 228) are shown that are differently shaped and/or bridge multiple actuation fingers.

For example, as shown in fig. 6I, a substantially rectangular bridging structure (e.g., bridging structure 234) is shown bridging three actuation fingers (e.g., actuation fingers 235, 236, 237). Further, as shown in fig. 6J, a substantially X-shaped bridging structure (e.g., bridging structure 238) is shown bridging one actuation finger (e.g., actuation finger 239). Additionally, as shown in fig. 6K, a substantially H-shaped bridging structure (e.g., bridging structure 240) is shown bridging one actuation finger (e.g., actuation finger 241). Further, as shown in fig. 6L, a substantially X-shaped bridging structure (e.g., bridging structure 242) is shown bridging three actuation fingers (e.g., actuation fingers 243, 244, 245).

Referring also to fig. 8, a detailed view of an out-of-plane actuator 252 is shown, in accordance with various embodiments of the present disclosure. Examples of out-of-plane actuators 252 may include, but are not limited to, piezoelectric actuators. The out-of-plane actuator 252 may be configured to provide actuation in a plurality of directions, including directions (e.g., the z-axis) orthogonal to the motion provided by the in-plane MEMS actuator 250. The out-of-plane actuator 252 may include a center stage 300 configured to allow, for example, connection of the photovoltaic device 26 (see fig. 3). The out-of-plane actuator 252 may also include an outer frame 302, an intermediate stage 304, an intermediate stage 306, actuation beams 308, 310, 312, and an electric flexure 314. The actuator beams 308, 310, 312 may be configured to connect the center stage 300, the intermediate stage 304, the intermediate stage 306, and the outer frame 302.

Although only one set of electric flexures is shown, this is for illustration purposes only and is not intended to limit the present disclosure, as other configurations are possible. For example, a set of electric flexures may also be included between the intermediate stages 304, 306, and/or a set of electric flexures may also be included between the intermediate stage 306 and the center stage 300. Although center station 300 is shown as being oval, other configurations are possible and should be considered to be within the scope of the present disclosure.

Due to the deformation of the actuation beams 308, 310, 312, a Z-axis (i.e., out-of-plane) motion of the center stage 300 of the out-of-plane actuator 252 may be generated, and the actuation beams 308, 310, 312 may be formed of a piezoelectric material (e.g., PZT (lead zirconate titanate), zinc oxide, or other suitable material) that may be configured to deflect in response to an electrical signal. The actuator beam 308 and the electric flexures 314 may be configured to meet various stiffness requirements and/or to allow the level of deformability required to achieve a desired level of z-axis motion while inhibiting x-axis and y-axis motion. The amount of actuation beam and electrical deflection at each level (i.e., each concentric ring in this example) may be varied to achieve a desired level of stiffness and/or flexibility and to provide a desired number of electrical connections.

The actuator beams 308, 310, 312 and/or the electric flex 314 may include cantilevers and/or hinges (not shown) to enable movement in an out-of-plane (z-axis) direction. As described above, piezoelectric materials can be used to achieve the desired deformation when an electrical signal is applied. The various beams (e.g., actuation beams 308, 310, 312) and the electrical flexures (e.g., electrical flexure 314) may include metal layers for guiding electrical signals.

The center station 300 may be divided into two or more discrete portions (e.g., center station portions 300A, 300B), wherein the shape of these discrete portions may vary according to design criteria. In addition, the intermediate stations 304, 306 may also be divided into two or more discrete portions. In such a configuration, when an electrical signal is applied to an actuator beam connected to center table portion 300A and/or center table portion 300B, the portion of center table 300 provided with the electrical signal may be moved out of plane (in the z-axis) to achieve a desired roll or pitch level.

Referring also to fig. 9A, a cross-sectional view of a two-actuator package is shown, according to various embodiments of the present disclosure. The out-of-plane actuator 252 may be connected to the printed circuit board 12 at the outer frame 302 by epoxy 350 or other suitable adhesive/material. In various embodiments, the printed circuit board 12 may form a portion of the package 10. The in-plane MEMS actuator 250 may be disposed on the out-of-plane actuator 252 and may be coupled to the outer frame 302 and the center table 300 of the out-of-plane actuator 252. The optoelectronic device 26 may be disposed on top of the in-plane MEMS actuator 250.

A retainer assembly 316 (which may include a glass window 318) may be disposed on top of the printed circuit board 12 or the in-plane MEMS actuator 250. Electrical connection 320 from the optoelectronic device 26 to the periphery of the MEMS in-plane actuator 250 may be accomplished, for example, by a standard COB wire bonding process, by a conductive epoxy/paste, by a MEMS bonding process, or by other suitable bonding means. The electrical connection 322 from the outer frame 30 of the in-plane MEMS actuator 250 to the pads 310 of the printed circuit board 12 may use the same bonding process as used for the electrical connection 306.

It can be appreciated that some embodiments of the package 10 may not include the out-of-plane actuator 252. In such embodiments, the in-plane MEMS actuator 250 may be mounted directly to the printed circuit board 12 by epoxy or by securing the comb drive sector (e.g., comb drive sector 106) of the microelectromechanical system (MEMS) actuator 24 and the fixed frame portion (e.g., fixed frame 156) of the outer frame 30 to the printed circuit board 12.

Referring also to fig. 9B, a cross-sectional detail view of a portion of the two actuator package shown in fig. 9A is shown. For embodiments of the package 10 that include an out-of-plane actuator 252, the out-of-plane actuator 252 may be electrically connected to elements outside of the package 10 by a conductive epoxy (or solder paste) disposed within the channels 352 formed in the in-plane MEMS actuator 250 and also by the plurality of conductive flexures 32 of the in-plane MEMS actuator 250.

In various embodiments, the electrical routing/signals of the out-of-plane actuator 252 may pass through the electrical flex 314 (see fig. 8) or may pass through the actuation beams 308, 310, and 312 and through the electrical contacts 354 (not shown in fig. 9B) electrically connected to the circuit board 12. The electrical signal may also pass through the in-plane MEMS actuator 250 through the channels 352, and the channels 352 may be filled with conductive epoxy, silver paste, or plating to achieve the desired conduction.

Referring also to fig. 10, a cross-sectional view of a portion of an out-of-plane actuator 252 (in a deformed position) and an in-plane MEMS actuator 250 is shown, in accordance with various embodiments of the present disclosure. The center stage 300 of the "deformed" out-of-plane actuator 252 may be connected to an in-plane MEMS actuator 250 that is connected to the optoelectronic device 26. An electrical signal may be applied to the actuation beams 308, 310, 312 and may cause deformation of the out-of-plane actuator 252. The flexibility of the plurality of conductive flexures 32 may be configured to enable tri-axial movement of the in-plane MEMS actuator 250 while achieving the flexibility and robustness requirements of the out-of-plane actuator 252.

The Z-axis "out-of-plane" motion of out-of-plane actuator 252 may be generated at least in part due to the deformation of actuation beams 308, 310, 312. As shown more clearly in fig. 11, the actuator beam 308 may deform when an electrical signal is applied to the poled piezoelectric material (e.g., PZT). Various suitable piezoelectric materials having different polarization patterns and characteristics may be used to achieve the desired level of deformation. Although not shown, the actuator beams 310, 312 (not shown) may be deformed similarly to the actuator beam 308. In some embodiments, the actuator beam 308 may be a composite material (e.g., comprising an upper material 400 and a lower material 402), wherein various materials may be used in combination to create a desired piezoelectric effect. Further embodiments may utilize different configurations of in-plane MEMS actuators 250 and out-of-plane actuators 252 to achieve additional degrees of freedom.

MEMS camera packaging (invention # 3)

As described above, some embodiments of the package 10 may not include the out-of-plane actuator 252, and in such embodiments, the in-plane MEMS actuator 250 may be mounted directly to the printed circuit board 12 by epoxy or by securing the comb drive sector (e.g., the comb drive sector 106) of the microelectromechanical system (MEMS) actuator 24 and the fixed frame portion (e.g., the fixed frame 156) of the outer frame 30 to the printed circuit board 12. Accordingly, the following discussion relates to such systems (i.e., camera packages) that do not include out-of-plane actuators.

Referring also to fig. 12, a cross-sectional view of a camera package (e.g., package 10) that does not include an out-of-plane actuator is shown. Thus, for this example, the package 10 is only capable of moving in two directions (e.g., the x-axis and the y-axis).

The package 10 may include a microelectromechanical system (MEMS) actuator 24 configurable (on a lower surface) to be connected to the printed circuit board 12. The printed circuit board 12 may include a recess 450 for receiving a microelectromechanical system (MEMS) actuator 24. The printed circuit board 12 may include a metal plate 452 to enable connection of a microelectromechanical system (MEMS) actuator 24 to the printed circuit board 12. Examples of the metal plate 452 may include a stainless steel plate positioned within the groove 450. In particular, the metal plate 452 may be epoxidized/attached within the recess 450 of the printed circuit board 12 and may enable a smooth planar surface for connecting the microelectromechanical system (MEMS) actuator 24 to the printed circuit board 12.

An image sensor assembly (e.g., optoelectronic device 26) may be coupled to an upper surface of a microelectromechanical system (MEMS) actuator 24. For example, the optoelectronic device 26 may be epoxidized/attached to the periphery 110 of the MEMS actuation core 34. Thus, by connecting the optoelectronic device 26 to the microelectromechanical system (MEMS) actuator 24, the optoelectronic device 26 can be moved along the x-axis and the y-axis to achieve various operations (e.g., image stabilization).

A retainer assembly (e.g., retainer assembly 454) may be connected to a microelectromechanical system (MEMS) actuator 24 and positioned relative to the MEMS actuator 24, wherein the purpose of the retainer assembly 454 may be to cover and buffer (snub) the MEMS actuator 24. For example, rather than positioning the holder assembly 454 relative to the printed circuit board 12, the holder assembly 454 may be positioned relative to a microelectromechanical system (MEMS) actuator 24. Thus, by positioning the holder assembly 454 relative to the microelectromechanical system (MEMS) actuator 24, any irregularities associated with the printed circuit board 12 may be eliminated.

The autofocus actuator 456 may be coupled to the holder assembly 454, and the lens assembly 458 may be coupled to the autofocus actuator 456. An IR filter 460 may be positioned between the autofocus actuator 456 and the holder assembly 454 and may be configured to filter infrared light from an incident image prior to entering the optoelectronic device 26.

Referring also to fig. 13A-13B, the holder assembly 454 may include one or more impact action assemblies (e.g., impact action assembly 500) configured to define a maximum amount of z-axis movement of the microelectromechanical system (MEMS) actuator 24 in response to an action. In particular, the impact assembly 500 may be positioned near movable portions (e.g., the movable frame 152 and the movable ridge 154) of the microelectromechanical system (MEMS) actuator 24 so that z-axis motion of these movable portions may be controlled. For example, the maximum z-axis movement of the movable portions (e.g., movable frame 152 and movable ridge 154) of microelectromechanical system (MEMS) actuator 24 may be about 35 microns. Further, the holder assembly 454 may include one or more image sensor stop assemblies (e.g., sensor stop assembly 502) configured to buffer (snub) the optoelectronic device 26 and define a maximum z-axis movement amount of the optoelectronic device 26 in response to the action. For example, the maximum z-axis movement of photovoltaic device 26 may be about 40 microns. Specifically, the gap between the holder assembly 454 and the image sensor assembly (e.g., the optoelectronic device 26) may be about 195 microns, wherein wire bonding and epoxy may reduce the gap to about 40 microns.

Additionally, the holder assembly 454 may include one or more clearance slots (e.g., clearance slot 504) configured to provide clearance for one or more electrical connectors (e.g., plurality of conductive flexures 32) of the microelectromechanical system (MEMS) actuator 24. The retainer assembly 454 may also include one or more stiffening ribs (e.g., stiffening ribs 506) configured to bridge the one or more clearance slots (e.g., clearance slots 504) and stiffen the retainer assembly 454. The holder assembly 454 may also include one or more spacer assemblies (e.g., spacer assembly 508) configured to position the holder assembly 454 relative to the microelectromechanical system (MEMS) actuator 24. In particular, the spacer assembly 508 may be in contact with the outer frame 30 of the microelectromechanical system (MEMS) actuator 24.

Two-axis MEMS camera packaging component (invention # 4)

As noted above, some embodiments of the package 10 may not include the out-of-plane actuator 252, and the following discussion relates to such systems that do not include an out-of-plane actuator (i.e., camera packages).

Referring also to fig. 14, a method 550 of fabricating a microelectromechanical system (MEMS) assembly may include 552 mounting a microelectromechanical system (MEMS) actuator 24 to a metal plate 452. An image sensor assembly (e.g., optoelectronic device 26) may 554 be mounted to microelectromechanical system (MEMS) actuator 24. The image sensor assembly (e.g., the optoelectronic device 26) may be 556 electrically connected to a microelectromechanical system (MEMS) actuator 24, forming a microelectromechanical system (MEMS) subassembly.

552 mounting the microelectromechanical system (MEMS) actuator 24 to the metal plate 452 may include 558 applying epoxy to the metal plate 452, 560 positioning the microelectromechanical system (MEMS) actuator 24 on the epoxy, and 562 curing the epoxy. In other embodiments, other suitable glues or other adhesives may be used.

554 mounting an image sensor assembly (e.g., optoelectronic device 26) to a microelectromechanical system (MEMS) actuator 24 may include 564 applying epoxy to the MEMS actuator 24, 566 positioning an image sensor (e.g., optoelectronic device 26) on the epoxy, and 568 curing the epoxy. In other embodiments, other suitable glues or other adhesives may be used.

556 electrically connecting the image sensor component (e.g., optoelectronic device 26) to a microelectromechanical system (MEMS) actuator may include 570 wire bonding the image sensor component (e.g., optoelectronic device 26) to the microelectromechanical system (MEMS) actuator 24.

A microelectromechanical system (MEMS) subassembly 572 can be mounted to the printed circuit board 12. Mounting 572 the microelectromechanical system (MEMS) subassembly to the printed circuit board 12 may include 574 applying an epoxy to the printed circuit board 12, 576 positioning the microelectromechanical system (MEMS) subassembly on the epoxy, and 578 curing the epoxy. In other embodiments, other suitable glues or other adhesives may be used. The printed circuit board 12 may include openings (or recesses) of various depths, and (in some embodiments) epoxy may be applied to the upper surface of the printed circuit board 12.

A microelectromechanical system (MEMS) subassembly 580 may be electrically connected to the printed circuit board 12. At 580 electrically connecting the microelectromechanical system (MEMS) subassembly to the printed circuit board 12 may include at 582 wire bonding the microelectromechanical system (MEMS) subassembly to the printed circuit board 12. 580 electrically connecting a microelectromechanical system (MEMS) subassembly to the printed circuit board 12 may further comprise 584 encapsulating the wire bonds in an epoxy.

The holder assembly 454 may be 586 mounted to a microelectromechanical system (MEMS) subassembly. 586 mounting the holder assembly 454 to a microelectromechanical system (MEMS) subassembly may include 588 applying an epoxy to the printed circuit board 12, 590 positioning the holder assembly onto the epoxy, and 592 curing the epoxy. For example, the holder assembly 454 may be placed on top of a microelectromechanical system (MEMS) subassembly, and an epoxy may be applied between the holder assembly 454 and the printed circuit board 12 (to connect the holder assembly 454 to the microelectromechanical system (MEMS) subassembly). Once the holder assembly 454 is positioned on top of the microelectromechanical system (MEMS) subassembly, the epoxy may be applied in the gap between the printed circuit board 12 and the holder assembly 454. The spacer assembly 508 can be used as a reference surface to contact a microelectromechanical system (MEMS) subassembly. In other embodiments, other suitable glues or other adhesives may be used.

Triaxial MEMS camera packaging assembly

As described above, some embodiments of the package 10 may include an out-of-plane actuator 252, and the following discussion relates to such systems (i.e., camera packages) that include an out-of-plane actuator.

Referring also to fig. 15, a method 600 of manufacturing a microelectromechanical system (MEMS) assembly may include 602 applying epoxy on the printed circuit board 12 for bonding the outer frame 302 of the out-of-plane actuator 252 to the printed circuit board 12. In other embodiments, other suitable glues or other adhesives may be used. The printed circuit board 12 may include openings (or recesses) of various depths, and (in some embodiments) epoxy may be applied to the upper surface of the printed circuit board 12.

The out-of-plane actuator 252 may be a z-axis piezoelectric actuator and may be mounted (directly or indirectly) on the printed circuit board 12. In other embodiments, another element is disposed between the out-of-plane actuator 252 and the printed circuit board 12. After the epoxy is cured, the outer frame 302 of the out-of-plane actuator 252 may be applied to the printed circuit board 12. The outer frame 302 of the out-of-plane actuator 252 may be constructed of a silicon material (which may have a coefficient of thermal expansion that matches that of the printed circuit board 12). Additionally/alternatively, the outer frame 302 may be constructed of a flexible material to compensate for any mismatch in thermal expansion.

After the out-of-plane actuator 252 is assembled, epoxy may be applied 606 to the center stage 300 and the outer frame 302 of the out-of-plane actuator 252. In other embodiments, other suitable glues or other adhesives may be used. The in-plane MEMS actuator 250 may be placed on the out-of-plane actuator 252 and the epoxy may be allowed to cure. After curing, the in-plane MEMS actuators 250 may be bonded to out-of-plane actuators 252 on the printed circuit board 12.

The out-of-plane actuator 252 may include conductive traces (conductive traces) that pass through the in-plane MEMS actuator 250 (as described above). Conductive epoxy or similar material may be provided 610 over associated holes on in-plane MEMS actuator 250 to connect and electrically connect to out-of-plane actuator 252, wherein the conductive epoxy is allowed to subsequently cure.

A thermal epoxy (or another suitable adhesive) may be applied 612 over the outer perimeter of the in-plane MEMS actuator 250, and then the optoelectronic device 26 may be attached 614 to the in-plane MEMS actuator 250. Various suitable epoxy resins or other adhesives may be used.

After curing to secure the optoelectronic device 26 to the in-plane MEMS actuator 250, electrical connection may be completed 616 by a standard COB process (or other suitable method). A protective epoxy may be applied 618 to the electrical connector to enhance the strength and robustness of the bond. Other protective materials may be used in other embodiments.

If particles are present on the optoelectronic device 26, they may be removed 620 by vibrating the optoelectronic device 154, wherein the holder 302 (which may include the glazing 304) may be 622 mounted to the circuit board 12 or the in-plane MEMS actuator 250.

Zipper actuator (invention # 5)

The discussion above relates to the use of, for example, a microelectromechanical system (MEMS) actuator 24 that includes a plurality of actuation fingers including movable actuation fingers 162B (connected to movable frame 152 and movable ridge 154B) and fixed actuation fingers 164B (connected to fixed frame 156 and fixed ridge 158). While the use of such finger-based MEMS actuators provides a high level of granularity and controllability, such granularity and controllability is generally not required. For example, some systems require that the system be in only one of two states (e.g., on/off, up/down). Examples of such systems may include, but are not limited to, shutter control systems (i.e., shutter open or closed) and telephoto lens systems (i.e., lenses in standard mode or zoom mode).

In this case, a zipper actuator may be used, as the zipper actuator provides good performance for a system requiring only two such positions. Referring also to FIG. 16, a microelectromechanical system (MEMS) assembly 650 can include a fixed stage 652 and a rigid stage 654. The at least one flexure 656 may be configured to slidably connect the fixed stage 652 and the rigid stage 654, thereby allowing the rigid stage 654 to be slidably displaced along the x-axis. At least one flexible electrode 658 is connected to and substantially perpendicular to one of the fixed and rigid stages 652, 654. And at least one rigid electrode 660 is connected to and substantially perpendicular to the other of the fixed stage 652 and the rigid stage 654.

The at least one flexible electrode 658 may be configured to be energized at a first voltage potential and the at least one rigid electrode 660 may be configured to be energized at a second voltage potential. Thus, by applying a voltage potential across the electrodes 658, 660, an electric field can be generated between the electrodes 658, 660, drawing the electrodes 658, 660 toward each other. Specifically, in the embodiment shown in fig. 16, the flexible electrode 658 will be pulled toward the rigid electrode 660. And when the flexible electrode 658 is flexible, the flexible electrode 658 will bend toward the rigid electrode 660 until the lower end of the flexible electrode 658 contacts the lower end of the rigid electrode 660. At this point, the flexure 656 may flex and allow the rigid land 654 to move toward the rigid electrode 660, allowing the entire flexible electrode 658 to "pull up" against the rigid electrode 660 and close any gap therebetween. The electrodes 658, 660 may each include an insulating layer 662 such that they do not short when the electrodes 658, 660 are initially in contact with each other. This in turn will allow the voltage potential described above to be maintained and allow the flexible electrode 658 to fully engage the rigid electrode 660.

As described above, microelectromechanical system (MEMS) assembly 650 can include at least one flexible electrode 658 and at least one rigid electrode 660. Thus, a microelectromechanical system (MEMS) assembly 650 can include two or more flexible electrodes (connected to and substantially orthogonal to one of the fixed and rigid stages) and two or more rigid electrodes (connected to and substantially orthogonal to the other of the fixed and rigid stages). For example, fig. 17A illustrates an embodiment in which a microelectromechanical system (MEMS) assembly 650 includes two rigid electrodes (e.g., rigid electrodes 700, 702) and two flexible electrodes (e.g., flexible electrodes 704, 706).

In general, the flexible electrodes (e.g., flexible electrodes 658, 704, 706) may be generally straight in shape (as shown in fig. 16, 17A). However, as shown in fig. 17B, these flexible electrodes may generally be curved in shape (e.g., flexible electrodes 708, 710) and may curve toward rigid electrodes 712, 714.

Additionally/alternatively, while the rigid electrodes (e.g., 660, 700, 702, 712, 714) are shown as being generally rectangular in shape, this is for illustrative purposes only and is not intended to limit the present disclosure as other configurations are possible. For example, as shown in fig. 17C, the rigid electrodes (e.g., rigid electrodes 716, 718) may include at least one surface that is not orthogonal to the fixed stage and/or rigid stage. For example, the rigid electrodes 716, 718 are shown as being pyramid-like, with portions near the stage to which they are connected being relatively wide and angled toward the flexible electrodes 720, 722.

To enhance the utility of microelectromechanical system (MEMS) assembly 650, microelectromechanical system (MEMS) assembly 650 may include a plurality of assemblies that may be arranged in a series configuration (as shown in fig. 18A) to enhance the maximum displacement of a rigid (i.e., movable) stage. Additionally, microelectromechanical system (MEMS) component 650 can include a plurality of components that can be arranged in a parallel configuration to enhance the strength/power of a rigid (i.e., movable) stage and/or in a parallel-series configuration (as shown in fig. 18B) to enhance the maximum displacement and strength/power of a rigid (i.e., movable) stage.

Slidable connecting assembly (invention # 7)

As is known in the art, various etching processes may be used in fabricating MEMS devices (e.g., microelectromechanical system (MEMS) actuator 24), wherein tens of these MEMS devices may be etched into a single silicon wafer. Automated machinery and assembly robots may be utilized to retrieve these MEMS devices from the wafer and perform the assembly process described above. It is therefore desirable to include some form of structure on the wafer that holds the MEMS devices in place on the wafer until they need to be assembled, at which point the structure should allow for easy removal of the MEMS devices from the wafer.

19A-19C, one embodiment of a slidable connection assembly that can be used to temporarily hold a MEMS device in place on a wafer until, for example, the MEMS device needs to be assembled. Accordingly, a microelectromechanical system (MEMS) device (e.g., microelectromechanical system (MEMS) actuator 24) may include one or more slidably connected assemblies (e.g., slidably connected assemblies 750) for releasably connecting the microelectromechanical system (MEMS) device to a wafer (e.g., wafer 752) from which the microelectromechanical system (MEMS) device is fabricated. In particular, the slidably connected assembly (e.g., slidably connected assembly 750) may be fabricated simultaneously with a microelectromechanical system (MEMS) device (e.g., microelectromechanical system (MEMS) actuator 24) and may be fabricated from the same wafer (e.g., wafer 752) from which the microelectromechanical system (MEMS) device (e.g., MEMS actuator 24) was fabricated. Thus, one or more of the slidable connection assemblies (e.g., slidable connection assembly 750) can include a portion of wafer 752 (e.g., a support post on wafer 752).

As described above, the microelectromechanical system (MEMS) actuator 24 may include a MEMS actuation core 34 and a MEMS electrical connector assembly (e.g., the outer frame 30) electrically connected to the MEMS actuation core 34 and configured to be electrically connected to a printed circuit board (e.g., the printed circuit board 12).

The one or more slidable connection assemblies (e.g., slidable connection assembly 750) can be any portion of a MEMS device positioned by slidable connection assembly 750. For example, the slidable connection assembly 750 may be part of the MEMS actuation core 34 and/or part of a MEMS electrical connector (e.g., the outer frame 30).

One or more of the slidably connected assemblies (e.g., slidably connected assembly 750) may be configured to enable easy removal of a microelectromechanical system (MEMS) device (e.g., microelectromechanical system (MEMS) actuator 24) from wafer 752 when assembly is desired, while securely positioning the microelectromechanical system (MEMS) device (e.g., microelectromechanical system (MEMS) actuator 24) on wafer 752 (until that point).

Thus, the one or more slidable connection assemblies (e.g., slidable connection assembly 750) may include one or more finger assemblies (e.g., device finger assemblies 754) on a microelectromechanical system (MEMS) device (e.g., microelectromechanical system (MEMS) actuator 24). The device finger assemblies 754 may be sized such that they do not extend beyond a suitable edge (e.g., edge 756) of, for example, a microelectromechanical system (MEMS) actuator 24, thereby allowing the MEMS actuator 24 to rest or lie tightly on another device/system.

The one or more slidable connection assemblies (e.g., slidable connection assembly 750) may also include one or more finger assemblies (e.g., wafer finger assemblies 758) on wafer 752. The one or more slidable connection assemblies (e.g., slidable connection assembly 750) may also include one or more socket assemblies (e.g., wafer socket assembly 760) on wafer 752 configured to receive the one or more finger assemblies (e.g., device finger assemblies 754) on a microelectromechanical system (MEMS) device (e.g., microelectromechanical system (MEMS) actuator 24).

One or more socket assemblies (e.g., wafer socket assembly 760) on wafer 752 may include a bridging structure (e.g., wafer bridging structure 762) configured to bridge at least two fingers (selected from wafer finger assemblies 758) on wafer 752 to form one or more socket assemblies (e.g., wafer socket assembly 760) therebetween.

The one or more slidable connection assemblies (e.g., slidable connection assembly 750) may also include one or more socket assemblies (e.g., device socket assembly 764) on microelectromechanical system (MEMS) devices (e.g., microelectromechanical system (MEMS) actuator 24) configured to receive one or more finger assemblies (e.g., wafer finger assemblies 758) on wafer 752.

One or more socket assemblies (e.g., device socket assembly 764) on a microelectromechanical system (MEMS) device (e.g., microelectromechanical system (MEMS) actuator 24) may include a bridging structure (e.g., device bridging structure 766) configured to bridge at least two fingers (selected from device finger assemblies 754) of the microelectromechanical system (MEMS) device (e.g., MEMS) actuator 24) to form one or more socket assemblies (e.g., device socket assembly 764) therebetween.

In fabricating the crossover structures 762, 766, a film patch may be deposited on top of the overlapping area of the fingers (e.g., device finger assembly 754 and wafer finger assembly 758). Specifically, a film patch may be attached to bridge three fingers (e.g., for wafer bridge 762, one device finger assembly, and two wafer finger assemblies), wherein the film is separated from one device finger assembly (in this example) so that the device finger assembly may be removed from the appropriate wafer socket assembly 760. The sacrificial layer 768 may be composed of a polysilicon material and may be removed during the release process and may leave a gap 770 allowing removal of the device finger assembly from the appropriate wafer socket assembly 760.

General purpose:

in general, the various operations of the methods described herein may be implemented using or may belong to the components or features of various systems and/or devices, as well as their respective components and sub-components, described herein.

In some cases, the presence of enlarged words and phrases such as "one or more," "at least," "but not limited to," or other similar phrases should not be construed to mean that a narrower case is intended or required without such enlarged phrases.

In addition, the various embodiments set forth herein are described in terms of example block diagrams, flowcharts, and other illustrations. It will be apparent to those of ordinary skill in the art after reading this document that the illustrated embodiments and their various alternatives may be implemented without limitation to the illustrated examples. For example, block diagrams and their accompanying description should not be construed as mandating a particular architecture or configuration.

While various embodiments have been described above, it should be understood that they have been presented by way of example only, and not limitation. Likewise, the various figures may depict example structures or other configurations for the present disclosure, which are to aid in understanding the features and functionality that may be included in the present disclosure. The disclosure is not limited to the example structures or configurations shown, but may be implemented using a variety of alternative structures and configurations to achieve the desired features. Indeed, it will be apparent to those skilled in the art how to implement alternative functional, logical, or physical divisions and configurations to implement the desired features of the present disclosure. In addition, with regard to the flow diagrams, operational descriptions, and method claims, the order of the steps presented herein should not force the various embodiments to perform the recited functions in the same order unless the context indicates otherwise.

While the present disclosure has been described above in terms of various example embodiments and implementations, it should be understood that the various features, aspects, and functions described in one or more individual embodiments are not limited in applicability to the particular embodiment in which they are described, but rather may be applied to one or more other embodiments of the present disclosure, alone or in various combinations, whether or not such embodiments are described and whether or not such features are presented as part of a described embodiment. Thus, the breadth and scope of the present disclosure should not be limited by any of the above-described exemplary embodiments, and those skilled in the art will recognize that various changes and modifications can be made to the foregoing description within the scope of the following claims.

Those skilled in the art will appreciate that the present disclosure may be implemented as a method, system, or computer program product. Accordingly, the present disclosure may take the form of an entirely hardware embodiment, an entirely software embodiment (including firmware, resident software, micro-code, etc.) or an embodiment combining software and hardware aspects that may all generally be referred to herein as a "circuit," module "or" system. Furthermore, the present disclosure may take the form of a computer program product on a computer-usable storage medium having computer-usable program code embodied in the medium.

Any suitable computer-usable or computer-readable medium may be utilized. The computer-usable or computer-readable medium may be, for example but not limited to, an electronic, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or propagation medium. More specific examples (a non-exhaustive list) of the computer-readable medium could include the following: an electrical connection having one or more wires, a portable computer diskette, a hard disk, a Random Access Memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disc read-only memory (CD-ROM), an optical storage device, a transmission media such as those supporting the Internet or an intranet, or a magnetic storage device. The computer-usable or computer-readable medium may also be paper or another suitable medium upon which the program is printed, as the program may be electronically captured, via, for instance, optical scanning of the paper or other medium, then compiled, interpreted, or otherwise processed in a suitable manner, if necessary, and then stored in a computer memory. In the context of this document, a computer-usable or computer-readable medium may be any medium that can contain, store, communicate, propagate, or transport the program for use by or in connection with the instruction execution system, apparatus, or device. The computer-usable medium may include a propagated data signal with the computer-usable program code embodied therewith, either in baseband or as part of a carrier wave. The computer usable program code may be transmitted using any appropriate medium, including but not limited to the internet, wireline, optical fiber cable, RF, etc.

Computer program code for carrying out operations of the present disclosure may be written in an object oriented programming language such as Java, smalltalk or c++, or the like. However, the computer program code for carrying out operations of the present disclosure may also be written in conventional procedural programming languages, such as the "C" programming language or any other programming language. The program code may execute entirely on the user's computer, partly on the user's computer, as a stand-alone software package, partly on the user's computer, partly on a remote computer or entirely on the remote computer or server. In the latter scenario, the remote computer may be connected to the user's computer through a local/wide area network/the Internet (for example, network 18).

The present disclosure is described with reference to flowchart illustrations and/or block diagrams of methods, apparatus (systems) and computer program products according to embodiments of the disclosure. It will be understood that each block of the flowchart illustrations and/or block diagrams, and combinations of blocks in the flowchart illustrations and/or block diagrams, can be implemented by computer program instructions. These computer program instructions may be provided to a processor of a general purpose computer/special purpose computer/other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create means for implementing the functions/acts specified in the flowchart and/or block diagram block or blocks.

These computer program instructions may also be stored in a computer-readable memory that can direct a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer-readable memory produce an article of manufacture including instruction means which implement the function specified in the flowchart and/or block diagram block or blocks.

The computer program instructions may also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer implemented process such that the instructions which execute on the computer or other programmable apparatus provide steps for implementing the functions/acts specified in the flowchart and/or block diagram block or blocks.

The flowcharts and block diagrams in the figures may illustrate the architecture, functionality, and operation of possible implementations of systems, methods and computer program products according to various embodiments of the present disclosure. In this regard, each block in the flowchart or block diagrams may represent a module, segment, or portion of code, which comprises one or more executable instructions for implementing the specified logical function(s). It should also be noted that, in some alternative implementations, the functions noted in the block may occur out of the order noted in the figures. For example, two blocks shown in succession may, in fact, be executed substantially concurrently, or the blocks may sometimes be executed in the reverse order, depending upon the functionality involved. It will also be noted that each block of the block diagrams and/or flowchart illustration, and combinations of blocks in the block diagrams and/or flowchart illustration, can be implemented by special purpose hardware-based systems which perform the specified functions or acts, or combinations of special purpose hardware and computer instructions.

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the disclosure. As used herein, the singular forms "a", "an", and "the" include plural referents unless the context clearly dictates otherwise. It will be further understood that the terms "comprises" and/or "comprising," when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof.

The corresponding structures, materials, acts, and equivalents of all means or step plus function elements in the claims below are intended to include any structure, material, or act for performing the function in combination with other claimed elements as specifically claimed. The description of the present disclosure has been presented for purposes of illustration and description, but is not intended to be exhaustive or limited to the disclosure in the form disclosed. Many modifications and variations will be apparent to those of ordinary skill in the art without departing from the scope and spirit of the disclosure. The embodiments were chosen and described in order to best explain the principles of the disclosure and its practical application, to thereby enable others skilled in the art to understand the invention and various embodiments with various modifications as are suited to the particular use contemplated.

Many embodiments have been described. Having described the disclosure in detail and by reference to embodiments thereof, it will be apparent that modifications and variations are possible without departing from the scope of the disclosure defined in the appended claims.

Claims

1. A microelectromechanical system (MEMS) actuator, comprising:

a first set of actuation fingers;

a second set of actuation fingers;

a first bridging structure configured to connect at least two of the first set of actuating fingers while bridging at least one of the second set of actuating fingers; and

a second bridging structure configured to connect the at least two fingers of the second set of actuating fingers while bridging the at least one finger of the first set of actuating fingers, wherein the second bridging structure is configured to bridge the at least one finger of the first set of actuating fingers at a distance configured to define a maximum level of first axis/second direction deflection of the at least two fingers of the second set of actuating fingers.

2. The microelectromechanical system (MEMS) actuator of claim 1, wherein the first bridging structure is configured to bridge at least one finger of the second set of actuation fingers by a distance configured to define a maximum level of first axis/first direction deflection of the at least one finger of the second set of actuation fingers.

3. The microelectromechanical system (MEMS) actuator of claim 2, wherein the first cross-over structure is configured to define a first gap between the first cross-over structure and at least one finger of the second set of actuation fingers, wherein the first gap is in a range of 0.1 μιη and 5 μιη.

4. The microelectromechanical system (MEMS) actuator of claim 1, wherein the second bridge is configured to define a first gap between the second bridge and at least one finger of the first set of actuation fingers, wherein the first gap is in a range of 0.1 μιη and 5 μιη.

5. The microelectromechanical system (MEMS) actuator of claim 1 wherein the first set of actuation fingers is a set of fixed actuation fingers.

6. The microelectromechanical system (MEMS) actuator of claim 1 wherein the second set of actuation fingers is a set of movable actuation fingers.

7. The microelectromechanical system (MEMS) actuator of claim 6 wherein the second set of actuation fingers is bi-directionally displaceable on a second axis and substantially non-displaceable on a third axis.

8. The microelectromechanical system (MEMS) actuator of claim 1 wherein the first set of actuation fingers is comprised of a silicon material.

9. The microelectromechanical system (MEMS) actuator of claim 1 wherein the second set of actuation fingers is comprised of a silicon material.

10. The microelectromechanical system (MEMS) actuator of claim 1 wherein the first crossover structure is comprised of a metallic material.

11. The microelectromechanical system (MEMS) actuator of claim 1, wherein the second crossover structure is comprised of a metallic material.

12. The microelectromechanical system (MEMS) actuator of any of claims 1-11, wherein the first bridging structure is to prevent the at least two fingers of the first set of actuating fingers from moving downward and the second bridging structure is to prevent the at least one finger of the first set of actuating fingers from moving upward.

13. A microelectromechanical system (MEMS) actuator, comprising:

a first set of actuation fingers;

a second set of actuation fingers;

a first bridging structure configured to connect at least two fingers of the first set of actuating fingers while bridging at least one finger of the second set of actuating fingers, wherein:

the first bridging structure is configured to bridge at least one finger of the second set of actuating fingers by a distance configured to define a maximum level of first axis/first direction deflection of the at least one finger of the second set of actuating fingers, an

The first bridging structure is configured to define a first gap between the first bridging structure and at least one finger of the second set of actuation fingers, wherein the first gap is in the range of 0.1 μm and 5 μm;

a second bridging structure configured to connect at least two of the second set of actuating fingers while bridging at least one of the first set of actuating fingers, wherein:

the second bridging structure is configured to bridge at least one finger of the first set of actuating fingers by a distance configured to define a maximum level of first axis/second direction deflection of at least two fingers of the second set of actuating fingers, an

The second bridging structure is configured to define a first gap between the second bridging structure and at least one finger of the first set of actuation fingers, wherein the first gap is in the range of 0.1 μm and 5 μm.

14. The microelectromechanical system (MEMS) actuator of claim 13 wherein the first set of actuation fingers is a set of fixed actuation fingers.

15. The microelectromechanical system (MEMS) actuator of claim 13 wherein the second set of actuation fingers is a set of movable actuation fingers.